Firearm firing mechanism with a disconnector pivotably mounted on the gear

ABSTRACT

A firing mechanism for firearms in which the sear spring is mounted so that its point of engagement with the sear can be switched farther from, or nearer to, the pivotal axis of the sear in order to increase or decrease the trigger pull. The sear spring is also mounted so that when the firing mechanism is used in a lever action, the sear spring also urges the latch for the finger lever into latching position. A disconnector is pivoted on the sear for rotation in one direction only with respect thereto, so that when the trigger engages the engagement surface on the disconnector, the firing mechanism is operable. After the gun is fired and while the trigger is pulled, the actuating lug on the trigger engages a convex surface on the underside of the disconnector pivoting it on the sear out of its operative position with respect thereto.

United States Patent Seecamp [54] FIREARM FIRING MECHANISM WITH A DISCONNECTOR PIVOTABLY MOUNTED ON THE GEAR [72] lnventor: Louis W. Seecamp, 561 Whitney Avenue,

New Haven, Conn. 0651 1 [22] Filed: Oct. 29, 1970 [21] Appl.No.: 84,956

[451 May 16, 1972 Primary Examiner-Benjamin A. Borchelt Assistant Examiner-C. T. Jordan [57] ABSTRACT A firing mechanism for fireanns in which the sear spring is mounted so that its point of engagement with the sear can be switched farther from, or nearer to, the pivotal axis of the sear in order to increase or decrease the trigger pull. The sear spring is also mounted so that when the firing mechanism is used in a lever action, the sear spring also urges the latch for the finger lever into latching position. A disconnector is pivoted on the sear for rotation in one direction only with respect thereto, so that when the trigger engages the engagement surface on the disconnector, the firing mechanism is operable. After the gun is fired and while the trigger is pulled, the actuating lug on the trigger engages a convex surface on the underside of the disconnector pivoting it on the sear out of its operative position with respect thereto.

7 Claims, 5 Drawing Figures PATENTEUMAY 16 I972 3. 662,483

sum 1 OF 2 INVENTOR LUZ/LS M/ 5CAWIP FIREARM FIRING MECHANISM WITH A DISCONNECTOR PIVOTABLY MOUNTED ON THE GEAR The present invention, relating to firearms, concerns a trigger pull adjustment switch and a new type of disconnector. The nature of this invention is embodied in the trigger mechanism shown in the drawings. Nevertheless, the trigger mechanism which is here used to illustrate the invention is not meant to represent the only way in which the invention can be embodied.

Whereas most trigger mechanism designs are made complicated through the use of many component structures, each structure performing a single or limited function, the present invention permits a simple trigger mechanism consisting of only a few strong parts. The number of springs, for example, is held to a minimum by having a spring serve more than one function. The sear spring acts not only to engage hammer and sear, but it also serves as the spring for the pivoted lever catch which retains the finger lever in the closed position. By altering the distance from the pivoted axis of the sear at which the sear spring exerts a force, trigger pull can be adjusted. Easily adjustable trigger pull is a great asset to the hunter. In winter, when a hunter is wearing gloves and has difficulty judging the pressure he exerts on the trigger, a heavy trigger pull is favored to prevent accidental discharge. A light trigger pull is advantageous in many other circumstances. An easily accessible bifurcated projection on the lower portion of the plunger housing functions as the trigger pull adjustment switch.

The coil spring that is positioned in a bore in the depending leg portion of the sear likewise has more than one function. Besides its primary function as the disconnector spring, it also functions as the trigger spring, which is made possible through the invention of a new type of disconnector, which is here illustrated by the drawings.

Of the drawings used for illustrative purposes:

FIG. I is a longitudinal sectional view of the lever action firearm trigger mechanism embodying the present invention. The hammer is shown in the cooked position, while the trigger and disconnector are engaged ready to fire.

FIG. 2 is a longitudinal sectional view of the same trigger mechanism with the hammer in the fired position.

FIG. 3 shows the hammer being returned to the cocked position by the retracted bolt. The mechanism with which the opened finger lever retracts the bolt is not shown, but may be assumed to be of a similar type to that found in US Pat. No. 3,092,924.

FIG. 4 is a view similar to FIGS. 1, 2 and 3. The finger lever is being returned to the closed or normal position after the retracted bolt has cocked the hammer. The hook on the finger lever is shown ready to engage a hook on the pivoted lever catch which holds the finger lever in the closed position. The actuating lug of the trigger is shown intersecting the convex lower surface of the somewhat crescent-shaped disconnector.

FIG. 5 is a fragmentary longitudinal sectional view of the trigger mechanism. The nose portion of the tubular telescoping plunger is trapped in the sear recess nearest the pivoted axis of the sear. ln FIGS. 1, 2, 3 and 4, the nose portion of the plunger is trapped in the sear recess furthest from the pivoted axis of the sear.

The lever action firearm used to illustrate the invention claimed is shown in part to consist of a stock 10, a frame 11, and a trigger mechanism assembly plate 12 which functions as that portion of the frame 11 on which the trigger mechanism is mounted. A finger lever 13 is pivotally connected to the trigger mechanism assembly plate 12 by a pivot pin 14.

The finger lever 13 is locked in the closed or normal position through the engagement of two hooks l5, 16. One hook 15 is located on the uppermost portion of the finger lever 13. The other hook 16 is part of the pivoted lever catch 17 which is pivotally connected to the trigger mechanism assembly plate 12 by a pivot pin 18. The hook 16 found on the pivoted lever catch 17 is pressured backwardly by a coiled sear spring 19 so that this hook 16 engages the hook 15 found on the finger lever 13 when the finger lever 13 is in the closed or normal position, as is shown in FIGS. 1 and 2. If the finger lever 13 is in the open position, as in FIG. 3, then a stop 20 on the trigger mechanism assembly plate 12 prevents the coiled sear spring 19 from pushing the pivoted lever catch 17 so far back that the hooks 15, 16 will not engage when the finger lever 13 is being returned to a closed or normal position (see FIG. 4).

The coiled sear spring 19 is positioned longitudinally between the end bore wall 21 of a tubular telescoping plunger 22 and the end bore wall 23 of the plunger housing 24. The coiled sear spring 19 serves not only to hold the sear 25 forward so that it engages the cocked hammer 26, but it simultaneously produces the forces necessary to hold the finger lever 13 in the closed or normal position. The plunger housing 24 is pivotally connected to the pivoted lever catch 17 by a pivot pin 27. The nose portion 28 of the telescoping plunger 22 is trapped in either of a pair of spaced recesses 29a, 29b located near the ear 30 of the sear. The sear 25 is pivotally connected to the trigger mechanism assembly plate 12 by a pivot pin 31. By bringing the finger lever 13 to the open position, as in FIG. 3, a bifurcated projection 32 constituting the lower portion of the plunger housing 24 is exposed. A coin or screwdriver head can then be inserted in the slot created by the bifurcation and through the exertion of a forward and upward pressure, the nose portion 28 of the telescoping plunger 22 is caused to be trapped in the recess 29a furthest from the pivot axis of the sear 25, as is shown in FIGS. 1, 2, 3, and 4. By exerting a rearward and downward pressure on the bifurcated projection 32 the nose portion 28 of the telescoping plunger 22 is caused to be trapped in the recess 29b nearest the pivot axis of the sear 25, as is shown in FIG. 5. Thus, by causing the nose portion 28 of the telescoping plunger 22 to be trapped in either of two spaced recesses 29a, 29b located at different distances from the pivoted axis of the sear 25, the magnitude of force can be regulated with which the sear surface 33 located on the nose portion 34 of the sear 25 engages the cocking notch 35 of the hammer 26. Consequently, the bifurcated projection 32 found on the plunger housing 24 functions as a trigger pull adjustment switch, for by regulating the magnitude of force with which the sear surface 33 engages the cocking notch 35, one naturally also regulates the magnitude of force required to disengage the sear surface 33 from the cocking notch 35, thereby causing the hammer 26 to be released from its cocked position (see FIGS. 1, 3, 4) and to be driven to the fired position (see FIG. 2).

The hammer 26, in this particular case, has been made less massive by positioning a hole 36 near its center. When the hammer 26, which is pivotally connected to the trigger mechanism assembly plate 12 by a pivot pin 37, is released from the cocked position, it transcribes an arc until striking the firing pin 38 enclosed by the bolt 39. The hammer 26 is propelled forwardly around its pivoted axis by a coiled hammer spring 40 which is positioned around a hammer guide pin 41 that is connected pivotally at one end to the hammer 26 by a pivot pin 42. The rear portion of the hammer guide pin 41 passes through a stationary guide 43 which is so shaped that it permits the hammer guide pin 41 to take on the different angles produced by cocked and fired positions of the hammer 26 (compare FIGS. 1, 3, 4 with FIG. 2.)

When the hammer 26 is in the cocked position (as shown in FIGS. 1, 3, 4), the tail tip 44 of the hammer guide pin 41 projects through an aperture 45 located in the front upper portion of the finger lever 13. Thus if a shooter runs his trigger finger against the front-upper-inner surface of the finger lever 13 when the finger lever 13 is in the normal or closed position and the hammer is cocked, he can feel the protruding tail tip 44 of the hammer guide pin 41. If the shooter does not feel the tail tip 44, then he knows the hammer 26 is not cocked.

When the hammer 26 is in the fired position (see FIG. 2), a stop 46 located on the trigger mechanism assembly plate 12 prevents the coiled sear spring 19 from rotating sear 25 so far in a clockwise direction, as viewed in the drawings, that the sear surface 33 and cooking notch 35 cannot engage when the hammer 26 is being brought into cooking position. A typical example of how cocking in this type of firearm is accomplished is demonstrated in US. Pat. No. 3,092,924, in which, as in this firearm, a downward and forward stroke of the finger lever 13 retracts the bolt 39 (see FIG. 3), causing it to move the hammer 26 rearward and downward to a cocked position. U.S. Pat. No. 3,092,924 is a good example of the type of firearm in which this trigger mechanism can be used.

In order to disengage the hammer 26 from the sear 25 a new type of disconnector 47 has been invented. This somewhat crescent-shaped disconnector 47 is pivotally connected to the depending leg portion 48 of the sear 25 by a pivot pin 49. A shoulder 50 on the sear 25 abuts the forward end 51 of the disconnector 47 when in the normal position (as shown in FIGS. 1, 2, 3, thereby preventing the counterclockwise rotation of the disconnector 47 about the pivot point which the drawings indicate is urged by a coil spring 52 positioned in a bore in the depending leg portion 48 of the sear 25. The coil spring 52 surrounds a pin-like retainer 53 which is ball-shaped at one end, that end being received in a recess 54 in the disconnector 47. When both finger lever 13 and disconnector 47 are in the normal position (see FIGS. 1, 2) an actuating lug 55 on the trigger 56 contacts the engagement surface 57 found on the tail portion of the crescent-shaped disconnector 47. By pulling the finger portion 58 of the trigger 56 backwardly, the actuating lug 55 of the trigger 56 is moved forwardly, since the finger portion 58 and actuating lug 55 are located on opposite sides of the pivot pin 59, which pivotally connects the trigger 56 to the finger lever 13. The forward motion of the actuating lug 55 against the engagement surface 57 of the disconnector 47 causes the sear 25 to turn counterclockwise, as viewed in the drawings, thereby disengaging the sear surface 33 of the sear 25 from the cocking notch 35 of the hammer 26. The hammer 26 thereupon strikes the firing pin 38.

In order to recock the hammer, the shooter strokes the finger lever 13 downwardly and forwardly until the finger lever 13 is in the position shown in FIG. 3. Should the shooter maintain a backward pressure on the finger portion 58 of the trigger S6,.the actuating lug 55 of the trigger 56 will intersect the convex underside of the crescent-shaped disconnector 47 as the finger lever 13 is returned to the normal or closed position, pivoting disconnector 47 clockwise on sear 25, as shown in FIG. 4. Since the actuating lug 55 of the trigger 56 must exert pressure directly against the engagement surface 57 of the sear 25 in order to disengage sear 25 from the hammer 26, the firearm cannot be fired until both trigger 56 and disconnector 47 return to their normal positions (see FIG. I). For this to occur, the shooter need only release the trigger 56. Once this is done, the coil spring 52 pivots the disconnector 47 counterclockwise to its normal position, forcing the actuating lug 55 rearward due to the convex underside surface on the disconnector 47, so that the actuating lug 55 and trigger 56 return to their normal positions (see FIG. I). The coil spring 52 thus also functions as the trigger spring.

What is claimed is:

1. In a firearm having a hammer pivoted between cooked and fired positions and a firing mechanism for holding said hammer in cocked position and releasing the same, the combination comprising a sear pivotally mounted into and out of cocking engagement with said hammer, sear-spring means resiliently urging said sear into cocking engagement, said hammer and sear having engagement surfaces such that upon pivoting said hammer from its firing position to its cocking position said sear is pivoted out and then into cocking position, a disconnector pivotally mounted on said sear between operative and inoperative positions, said disconnector and sear having a stop means for positively preventing pivotal movement of said disconnector beyond such operative position, disconnector spring means resiliently mounted on said sear for resiliently urging said disconnector into its operative position against said stop means, said disconnector having a trigger-engagement surface and a convex surface contiguous therewith and on the opposite side of said disconnector, said disconnector spring means and a trigger being mounted for engagement with said disconnector and having an actuating portion movable on actuation of said trigger into engagement with said disconnector engagement surface when said disconnector is in its operative position for pivoting said sear against said sear spring means in order to release said hammer, said actuating means being engageable with said convex surface on said disconnector when said hammer is cocked and while said trigger is actuated for pivoting said disconnector on said sear toward its inoperative position.

2. The combination defined in claim 1, wherein said trigger is mounted on a finger lever for movement out of engagement with said disconnector when said lever is operated for cocking said hammer.

3. The combination defined in claim 2, wherein said trigger is pivotally mounted on said finger lever.

4. The combination defined in claim 1, wherein said sear spring means comprises a spring plunger, a plunger housing in which said spring plunger is telescopically mounted, said plunger housing being pivotally mounted for swinging said plunger with respect to said sear, said sear having a plurality of plunger-receiving surfaces each disposed at different distances from the pivotal axis of said sear and said spring plunger being positionable on any of said plunger-receiving surfaces for increasing and decreasing the force required to release said hammer.

5. The combination defined in claim 4, which further includes a finger lever and a pivoted latch for retaining said finger lever in an operative position, said plunger housing being pivoted to said pivoted latch such that said sear spring means urges said pivoted latch into a latching position while at the same time urging said sear toward cocking engagement with said hammer.

6. The combination defined in claim I, which further includes a trigger guard disposed near said hammer and having an exposed surface, said hammer having a coil spring compressed between a portion of said hammer and a fixed guide surface spaced from the exposed surface on said trigger guard, an elongated guide pin pivoted at one end to said hammer within said coil spring, said fixed guide surface and said exposed surface both being apertured to receive said guide pin, the tail tip of said guide pin extending through said fixed guide surface when said hammer is in its cocking and firing positions and through said exposed surface on said trigger guard only when said hammer is in its cocked position.

7. The combination defined in claim 6, which includes a finger lever pivotal mounted for cocking said hammer, said trigger guard forming a part of said finger lever. 

1. In a firearm having a hammer pivoted between cocked and fired positions and a firing mechanism for holding said hammer in cocked position and releasing the same, the combination comprising a sear pivotally mounted into and out of cocking engagement with said hammer, sear-spring means resiliently urging said sear into cocking engagement, said hammer and sear having engagement surfaces such that upon pivoting said hammer from its firing position to its cocking position said sear is pivoted out and then into cocking position, a disconnector pivotally mounted on said sear between operative and inoperative positions, said disconnector and sear having a stop means for positively preventing pivotal movement of said disconnector beyond such operative position, disconnector spring means resiliently mounted on said sear for resiliently urging said disconnector into its operative position against said stop means, said disconnector having a trigger-engagement surface and a convex surface contiguous therewith and on the opposite side of said disconnector, said disconnector spring means and a trigger being mounted for engagement with said disconnector and having an actuating portion movable on actuation of said trigger into engagement with said disconnector engagement surface when said disconnector is in its operative position for pivoting said sear against said sear spring means in order to release said hammer, said actuating means being engageable with said convex surface on said disconnector when said hammer is cocked and while said trigger is actuated for pivoting said disconnector on said sear toward its inoperative position.
 2. The combination defined in claim 1, wherein said trigger is mounted on a finger lever for movement out of engagement with said disconnector when said lever is operated for cocking said hammer.
 3. The combination defined in claim 2, wherein said trigger is pivotally mounted on said finger lever.
 4. The combination defined in claim 1, wherein said sear spring means comprises a spring plunger, a plunger housing in which said spring plunger is telescopically mounted, said plunger housing being pivotally mounted for swinging said plunger with respect to said sear, said sear having a plurality of plunger-receiving surfaces each disposed at different distances from the pivotal axis of said sear and said spring plunger being positionable on any of said plunger-receiving surfaces for increasing and decreasing the force required to release said hammer.
 5. The combination defined in claim 4, which further includes a finger lever and a pivoted latch for retaining said finger lever in an operative position, said plunger housing being pivoted to said pivoted latch such that said sear spring means urges said pivoted latch into a latching position whIle at the same time urging said sear toward cocking engagement with said hammer.
 6. The combination defined in claim 1, which further includes a trigger guard disposed near said hammer and having an exposed surface, said hammer having a coil spring compressed between a portion of said hammer and a fixed guide surface spaced from the exposed surface on said trigger guard, an elongated guide pin pivoted at one end to said hammer within said coil spring, said fixed guide surface and said exposed surface both being apertured to receive said guide pin, the tail tip of said guide pin extending through said fixed guide surface when said hammer is in its cocking and firing positions and through said exposed surface on said trigger guard only when said hammer is in its cocked position.
 7. The combination defined in claim 6, which includes a finger lever pivotal mounted for cocking said hammer, said trigger guard forming a part of said finger lever. 